1. Chapter 23 Acids, Bases, and Salts

2. Have you seen these?

3. Section 1: Acids & Bases
Acid - (H+) removed in H2O.

4. Properties of Acids Taste sour Corrosive and can burn skin
React with litmus paper: red to yellow.

5. Common Acids Foods contains acids Citrus fruits citric acid
Vinegar, or acetic acid, is in pickled foods
2. You have hydrochloric acid (HCl) in your stomach.

6. Common Acids Four acids vital to industry.
Sulfuric acid - used in car batteries and the manufacturing of fertilizers
Phosphoric acid - used to manufacture detergents, fertilizers, and soft drinks
Nitric acid - used to manufacture fertilizers and explosive
Hydrochloric acid – used to clean steel

7. Bases Base - forms hydroxide ions (OH-) in water.
Compliments or opposites of acids

8. Properties of Bases Many are crystals Feel slippery
Strong bases are corrosive
litmus paper turns blue-purple

9. Common Bases
Ammonia & Sodium Hydroxide - are used in cleaners, fertilizers, rayon, nylon
Magnesium Hydroxide - medications
Aluminum Hydroxide – color fast fabrics

10. Solutions of Acids and Bases
Acid describes compounds that can be ionized in water to form hydronium ions
Base describes compounds that can form hydroxide ions in solution
Solutions of acids and solutions of bases are electric conductors to some extent

11. Discussion Questions
Why should a person never use taste testing to identify an acid or a base?

12. Answers Acids and Bases can be corrosive and cause damage to tissue
Sulfuric, phosphoric, nitric, hydrochloric

13. Section 2 Strength of Acids and Bases
The strength of an acid or a base depends on how completely a compound separates into ions when dissolving in water

14. Strong Acids and Strong Bases
A strong acid ionizes (or loses H+) almost completely in solution
A strong base dissociates (or forms OH-) completely in solution
Equations for strong acids and bases use a single arrow indicating ions are formed
Strong acids and bases conduct more electricity than weak ones

15. Weak Acids and Weak Bases
A weak acid/base only partly ionizes in solution
Equations for weak acids and bases use double arrows pointing in opposite directions, indicating an incomplete reaction
Dilute and concentrated are terms to describe the amount of acid or base dissolved

16. pH of a Solution
pH - a measure of the concentration of hydrogen ions (H+) in a solution or how acidic or basic it is
pH lower than 7 = acidic
pH greater than 7 = basic
pH exactly equal to 7 = neutral

17. pH of a Solution
pH is determined by a universal indicator paper or pH meter
Buffers – solutions containing
ions that react with
additional acids or
bases to minimize
their effects on pH.

18. Discussion Question
Is a strong acid the same thing as a concentrated acid? Why or Why Not?

19. Answer
Not necessarily the same; strength refers to ionization in a solution while concentration refers to the amount of acid or base dissolved

20. Section 3 Salts

21. Neutralization
Chemical reaction between an acid and a base taking place in a water solution
Hydronium ions from the acid combine with hydroxide ions from the base to produce neutral water

22. Salts
Salt - compound formed when the negative ions from an acid combine with the positive ions of a base
Salt is essential for many animals
Other salt uses include manufacturing of paint, rubber, glass, soap, detergents, and dry cell batteries

23. Titration
Used to determine the concentrations of an acidic or basic solution
A solution of known concentration is the standard solution
An acid/base indicator is added to an unknown solution
A color change that is constant
is the end point.

24. Soaps and Detergents Soaps
Are organic salts with polar and nonpolar ends.
The nonpolar, hydrocarbon end interacts with oil and dirt
The polar end helps oil and dirt dissolve in water
Detergents
Form more soluble salts with the ions in hard water

25. Esters
Come from alcohols that are not bases but have a hydroxyl (-OH) group
Esters are used in fruit flavorings and perfumes
Polyesters are synthetic fibers used to make fabrics

26. Discussion Question
What are two ways salts can form?

27. Answer
When an acid and a base combine their negative and positive ions
When an acid reacts with a metal